Heretofore, tool holders of the present type have either been right hand or left hand with the requirement that the corresponding insert be of the same hand for use with the particular holder. This necessitated using separate left and right hand insert designs on certain applications where the inserts would be of identical cutting design except for the necessity of left and right hand design to properly fit the corresponding holder. In the earlier U.S. Pat. No. 3,436,799, there is shown a holder of left hand design and used therewith a corresponding insert of left hand design. That patent relates to a means for securing a throw-away type cutting insert within a tool holder.
In groove cutting tools, a cutting insert having a plurality of identical cutting edges is commonly employed. These throw-away cutting inserts are generally mounted in a tool holder assembly which provides the support and feeding and guiding means for the cutter itself. Under conditions of constant production use and resulting cutting edge wear, these cutting inserts must be frequently removed from the tool holder, to either bring a fresh cutting edge of the multi-edged insert into position or to replace the entire insert with a new one when all of the cutting edges have been used.
In the foregoing patent, there is shown a tool holder of a left hand design. Due to the flat taper of the insert edges, it was necessary to use a left hand design insert. For a tool holder of right hand design, it was necessary to use an insert of right hand design. This required making inserts of left and right hand designs to fit the corresponding right and left hand holders.